separate paths for Emergency and Normal

[mshields]

Article 517 requires a separate path for normal from Life safety (and possibly critical) feeders. Is there a similar requirement in Article 700.

And if so, or even if not but as it pertains to 517, is separate path defined anywhere? i.e. if you run the normal feeder down the left side of a corridor and the Life Safety down the right side, is that a separate path. Obviously minus a strict definition, you'd certainly run the risk of the inspector saying its not. But anyway, you get the gist of my question.

Many thanks,

Mike

 

[Smart $]

700.10(B) requires emergency wiring be completely independent of other wiring and equipment with 5 UOP (unless otherwise permitted) conditions.

Searching 517 I saw separate used a lot, but I didn't see anything to it indicate separation by distance or path. Are you sure you are not confusing independent wiring separation with path and/or distance separation?

 

[steve66]

700.10(B) requires emergency wiring be completely independent of other wiring and equipment with 5 UOP (unless otherwise permitted) conditions.

Searching 517 I saw separate used a lot, but I didn't see anything to it indicate separation by distance or path. Are you sure you are not confusing independent wiring separation with path and/or distance separation?

I'm wondering the same thing. I'm not aware of any distance separation requirement between normal and emergency power feeders or branch circuits.

700 may have a requirement, but Hospitals are normally sprinklered, and there is an exception for spaces that have complete sprinkler coverage.

For both feeders and branch circuits, they eventually wind up in the same room, panel or ATS, so its impossible to keep them separated by any distance at the terminations.

 

[charlie b]

My interpretation (and I have no code article to back this up) is that running the wires in different conduits and through different boxes is all that is needed. The conduits can be suspended from the same support structure and be almost touching, and it would still comply.

 

[dkidd]

Article 517 requires a separate path for normal from Life safety (and possibly critical) feeders. Is there a similar requirement in Article 700.

Would you provide the reference?

 

[Ingenieur]

I read 517 as separate and distinct wiring/raceway (with some exceptions)
separated from and independent of other circuits
not that they have to be run physically separated by different paths thru the building

 

[mshields]

separate path

separate path

you're right that it doesn't use the verbiage "separate path". I'm referring to 517, 30 (C); Location of Essential Electrical System Components. Toward the end of the paragraph, it read "Feeders shall be located to provide physical separation of the feeders of the alternate source and from the feeders of the normal electrical source to prevent possible simultaneous interruption." It seems to me incidentally that there is an errant "and" in this sentence, but that notwithstanding, this is what I was referring to.

Now that I re-read it, I agree that it is clearly not so explicit as to state separate paths, but if all it means is separate conduit, isn't that covered elsewhere?

 

[steve66]

you're right that it doesn't use the verbiage "separate path". I'm referring to 517, 30 (C); Location of Essential Electrical System Components. Toward the end of the paragraph, it read "Feeders shall be located to provide physical separation of the feeders of the alternate source and from the feeders of the normal electrical source to prevent possible simultaneous interruption." It seems to me incidentally that there is an errant "and" in this sentence, but that notwithstanding, this is what I was referring to.

Now that I re-read it, I agree that it is clearly not so explicit as to state separate paths, but if all it means is separate conduit, isn't that covered elsewhere?

It looks like that's a newer requirement added in 2014, and revised in 2017.

It says separation of "feeders of the alternate source" from "feeders of the normal electrical source." So I think they are talking about the generator feeder and the normal power feeders going to the ATS. I do not think they are talking about the emergency feeders from the ATS, and the normal power feeders going to the branch panels, or whatever distribution its going too. In other words, it only applies on the line side the an ATS.

And, yes, how much separation is debatable. As I mentioned, they both eventually have to wind up at the ATS, so there will have to be at least one room where they are together.